1. Field of the Invention
This invention relates to treatment of tissue specimens and, more specifically, to the treatment of the tissue specimens in vivo.
2. Description of the Related Art
The prior art discloses devices and methods of isolating a tissue specimen while it remains in surrounding tissue. The prior art also discloses devices and methods of ablating or otherwise damaging a non-isolated tissue specimen in vivo. However, the prior art does not disclose, suggest, nor motivate combining the two concepts into one method or device. Additionally, the prior art does not disclose any synergistic effects of combining the two concepts.
It is disclosed in a paper entitled “The Loop Electrode: A New Device For US-guided Interstitial Tissue Ablation Using Radiofrequency Electrosurgery—An Animal Study,” T. Lorentzen et al., Min Invas Ther & Allied Technol 1996: 5:511-516, that a radiofrequency loop is used to perform interstitial tissue ablation. The device was inserted into calf livers and rotated to interstitially cut off lesions. The paper reviews minimally invasive tissue ablation techniques, such as intraoperative cryosurgery and percutaneous methods such as laser, microwaves, radiofrequency electrosurgery, and injection of ethanol or hot saline. The paper also reviews high-focused ultrasound as an example of a non-invasive method. The paper does not disclose, suggest, nor motivate combining the use of a radiofrequency loop with other tissue ablation methods.
A procedure is disclosed in a paper entitled “Interstitial Hyperthermia Of Colorectal Liver Metastases With A US-guided Nd-YAG Laser with a Diffuser Tip: A Pilot Clinical Study,” C. Nolsoe et al., Radiology, 1993; 187:333-337, that involves placing a laser fiber in the center of a tumor and irradiating the tumor to achieve hyperthermia ablation. It is also disclosed to use ultrasound to monitor the temperature of the tumor during the method. The paper discloses a charred border region about the tissue specimen and a coagulated region beyond the charred border. The paper does not disclose any concerns associated with ablating a nonisolated tissue specimen. The paper does not disclose, suggest, nor motivate combining the use of lasers with other tissue ablation methods.
It is disclosed in a paper entitled “Phototherapy of Tumors,” S. G. Brown, World J. Surg. 7, 700-709, 1983, the use of the chemical hematoporphyrin derivative (HpD) in conjunction with a dye laser for tumor therapy. The HpD/dye laser method is not thermal, as is the case with most laser methods, but depends on the production of singlet oxygen by activated HpD. The paper discloses the promise of the HpD/dye laser methods—but with no disclosure, suggestion, or motivation to isolate the tissue specimen prior to treatment. The paper discloses the problems associated with unacceptable damage to surrounding tissue during thermal laser methods.
It is disclosed in a paper entitled “Clinical Thermochemotherapy: A Controlled Trial In Advanced Cancer Patients,” F. K. Storm et al, Cancer 53:863868, 1984, to combine hyperthermia and chemotherapy for increased drug uptake of cancer cells. The hyperthermia was administered using a magnetrode magneticloop induction device. The paper does disclose the beneficial of preserving the tissue surrounding the tissue specimen, which in the disclosed method is due to coincident vascular occlusion. It does not disclose, motivate, or suggest direct methods of severing vascular connections between a tissue specimen and surrounding tissue, in conjunction with other methods of tissue specimen ablation.
It is disclosed in a paper entitled “Liver Photocoagulation With Diode Laser (805 nm) Vs Nd:YAG Laser (1064 nm),” S. L. Jacques et al., SPIE Vol. 1646 LaserTissue Interaction 111 (1992), p. 107-117, that laser treatment results in radially expanding regions of tissue damage. The paper does not disclose, suggest, nor motivate isolating the tissue specimen targeted for necrosis and any result that may have with reducing damage to surrounding tissue.
It is disclosed in a paper entitled “MR Imaging Of Laser-Tissue Interactions,” F. A. Jolesz, Radiology 1989; 168:249-253, that thermal transfer and damage to surrounding tissue during hyperthermia treatment should be monitored. The paper also discloses that circulatory cooling, among other parameters, affects energy deposition. The paper does not disclose, suggest, nor motivate that isolating the tissue specimen prior to hyperthermia treatment. This information is similarly disclosed in a paper entitled “Temperature Mapping With MR Imaging Of Molecular Diffusion: Application to Hyperthermia,” D. L. Bihan, Radiology 1989; 171: 853-857.
Therefore, the prior art discloses damage occurs to tissue surrounding a tissue specimen to be treated. What is needed is a device and method for reducing damage to the surrounding tissue. What is also needed is a device and method with increased efficiency for damaging the tissue specimens.